Such was the most recent stroke of good news in the potent, enduring tale of the Rockabye Baby series, which for 11 years and 78 albums has tried to alleviate one of the worst parts of being a parent — the music — with lullabied instrumental covers of songs from, you know, real bands. The Beyoncé version is the latest in a list that includes Prince, the Beatles, Springsteen, the Pixies, David Bowie, Eminem, the Cure, Guns N’ Roses, Rush, Kanye West, Radiohead, Adele, Cyndi Lauper, Tool and Iron Maiden. (If you think you had a weird day at work, imagine trying to coax “The Number of the Beast” out of a harp and glockenspiel.)